Hey guys, i got a question regarding my transmission in my 95 GMC Sierra 4x4, 305 V8. Last weekend my wife and i went camping and everything went o.k, well except for a tire blowout on the camper and other things, but my truck ran great and pulled the camper nicely without effort. And by the way my camper is a 16 Ft Prowler.
Anyhow, we towed the camper to the camping site and back without any issues. The next day my wife and i brought the camper to my father in-law to get a few things fixed. One being the tennis ball size hole in the floor from the blowout. Anyway, we visited with family for about 3 hours then decided we were going home. After leaving the camper there till the issues were fixed we hoped in the truck and started driving home. Once on the highway i hit my cruising speed of 100 KPH and everything was alright for the first 10 minutes. After a short while i noticed my speedometer jumping between 100 KPH and 90 KPH. Thinking what hell is going on i ignored it for a bit thinking it was a glitch and it would clear itself. A short while later i hear the transmission downshift then upshift shortly after that, rpm's fluctuating between 2300 rpm's 2000 rpm's. Not dramatic or anything but noticeable. Wondering what's going on i noticed the speedometer still jumping all over the place. Now starting to worry a bit i glance over at the rpm gauge and i see it go up for 1-2 seconds then back down again, obviously hearing the transmission shift at the same time. Now in a bit of a worry and wondering what is happening everything seems fine for about 10 seconds then wham, it downshifts then upshifts again. Fearing something was wrong with my tranny and fearing to destroy it i pull over to the side of the road to see what the hell is going on.
Once pulled over i pop the hood and check the tranny fluid, seems alright. So i check it several more times. After about the third time i pull the dipstick and see bubbles in the tranny fluid. Not knowing what was going on i call my father in law and tell him what's up. After a brief conversation he tells me the upshifting and downshifting is a result of the tranny overheating. After explaining to him that it looks o.k he decides to come find me on the highway and look for himself. After about 30 minutes of sitting on the highway he finally shows up and takes a look and comes up to the same conclusion, tranny fluid seems fine. After a short while he says let's take it for a short spin and see what it's doing. So we hop in head off down the highway.
Once we start accelerating down the highway the truck seems fine until it goes to shift into 3rd, nothing, it won't shift. Now baffled he takes a few more runs and the same thing, it won't shift into 3rd. Now figuring there's something wrong we opt to head back to his place and he'd ask his mechanic. As we hop in the truck for the slow drive back as we start accelerating it won't go into 2nd. Now completely confused my father in-law drives real slow accelerating a few clicks every few minutes. After about 15 minutes the truck finally manages to shift through all 3 gears and hitting 80 KPH. Not wanting to push it we cruise into town holding this speed without a problem, though the speedo is still jumping between 80, 60, 40, and 0 KPH. Once almost in town the speedo magically starts working again and the truck seems to be working fine going down local streets. However, at stops i could tell something was wrong as each time he hit the gas it sounded like it was lagging and being sluggish. After we finally get it to his house we check the tranny fluid again and it had bubbles in the fluid again. Now stumped we turn the truck off and leave it until he can ask his mechanic what's going on.
Next day my father in-law text's me and says: Do you haul the camper is (D) or in 3rd. So i say Drive, (D). Then he says the mechanic says to try changing the oil and filter to see if that helps first. So i say o.k. the next day we head over to his place and start talking about the truck when all of a sudden he says hey i got something to tell you. When you haul a trailer the mechanic says you're suppose to drive in third not Overdrive, (D). I'm like oh, yeah well i do that with my car but it has an electronic push button style overdrive. I told him my truck doesn't have a regular drive feature so i didn't think it had one, so i drove in regular drive. He then proceeds to tell me the mechanic said if it doesn't have just drive then 3rd is your drive. After pondering this over a bit i couldn't fathom the idea of 3rd being your drive. Anyhow, after agreeing with him i tell him my individual gears 1 and 2 don't go into gear with the shift selector. He then goes oh, how long has it been like that..? And i said since I've had it. Confused we talked a bit and says he'd ask the mechanic.
Anyway, I'm sorry for the long explanation here, but I'm trying to understand what's going on with my truck. And for some reason I can't for the love of me figure out how 3rd is my drive. Is there like a secret drive button on the shiter or gear that I'm not aware of..? Can anyone help me and possibly tell me what's going with my truck. And if anything do you think it's serious to the point where i need tranny work..? Any and all help is greatly appreciated.
Thanks again.
Anyhow, we towed the camper to the camping site and back without any issues. The next day my wife and i brought the camper to my father in-law to get a few things fixed. One being the tennis ball size hole in the floor from the blowout. Anyway, we visited with family for about 3 hours then decided we were going home. After leaving the camper there till the issues were fixed we hoped in the truck and started driving home. Once on the highway i hit my cruising speed of 100 KPH and everything was alright for the first 10 minutes. After a short while i noticed my speedometer jumping between 100 KPH and 90 KPH. Thinking what hell is going on i ignored it for a bit thinking it was a glitch and it would clear itself. A short while later i hear the transmission downshift then upshift shortly after that, rpm's fluctuating between 2300 rpm's 2000 rpm's. Not dramatic or anything but noticeable. Wondering what's going on i noticed the speedometer still jumping all over the place. Now starting to worry a bit i glance over at the rpm gauge and i see it go up for 1-2 seconds then back down again, obviously hearing the transmission shift at the same time. Now in a bit of a worry and wondering what is happening everything seems fine for about 10 seconds then wham, it downshifts then upshifts again. Fearing something was wrong with my tranny and fearing to destroy it i pull over to the side of the road to see what the hell is going on.
Once pulled over i pop the hood and check the tranny fluid, seems alright. So i check it several more times. After about the third time i pull the dipstick and see bubbles in the tranny fluid. Not knowing what was going on i call my father in law and tell him what's up. After a brief conversation he tells me the upshifting and downshifting is a result of the tranny overheating. After explaining to him that it looks o.k he decides to come find me on the highway and look for himself. After about 30 minutes of sitting on the highway he finally shows up and takes a look and comes up to the same conclusion, tranny fluid seems fine. After a short while he says let's take it for a short spin and see what it's doing. So we hop in head off down the highway.
Once we start accelerating down the highway the truck seems fine until it goes to shift into 3rd, nothing, it won't shift. Now baffled he takes a few more runs and the same thing, it won't shift into 3rd. Now figuring there's something wrong we opt to head back to his place and he'd ask his mechanic. As we hop in the truck for the slow drive back as we start accelerating it won't go into 2nd. Now completely confused my father in-law drives real slow accelerating a few clicks every few minutes. After about 15 minutes the truck finally manages to shift through all 3 gears and hitting 80 KPH. Not wanting to push it we cruise into town holding this speed without a problem, though the speedo is still jumping between 80, 60, 40, and 0 KPH. Once almost in town the speedo magically starts working again and the truck seems to be working fine going down local streets. However, at stops i could tell something was wrong as each time he hit the gas it sounded like it was lagging and being sluggish. After we finally get it to his house we check the tranny fluid again and it had bubbles in the fluid again. Now stumped we turn the truck off and leave it until he can ask his mechanic what's going on.
Next day my father in-law text's me and says: Do you haul the camper is (D) or in 3rd. So i say Drive, (D). Then he says the mechanic says to try changing the oil and filter to see if that helps first. So i say o.k. the next day we head over to his place and start talking about the truck when all of a sudden he says hey i got something to tell you. When you haul a trailer the mechanic says you're suppose to drive in third not Overdrive, (D). I'm like oh, yeah well i do that with my car but it has an electronic push button style overdrive. I told him my truck doesn't have a regular drive feature so i didn't think it had one, so i drove in regular drive. He then proceeds to tell me the mechanic said if it doesn't have just drive then 3rd is your drive. After pondering this over a bit i couldn't fathom the idea of 3rd being your drive. Anyhow, after agreeing with him i tell him my individual gears 1 and 2 don't go into gear with the shift selector. He then goes oh, how long has it been like that..? And i said since I've had it. Confused we talked a bit and says he'd ask the mechanic.
Anyway, I'm sorry for the long explanation here, but I'm trying to understand what's going on with my truck. And for some reason I can't for the love of me figure out how 3rd is my drive. Is there like a secret drive button on the shiter or gear that I'm not aware of..? Can anyone help me and possibly tell me what's going with my truck. And if anything do you think it's serious to the point where i need tranny work..? Any and all help is greatly appreciated.
Thanks again.
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